The concept behind StockTwits is simple — basically, if you tweet using a “$” symbol to indicate a stock, that message will be pulled into the StockTwits, making it an easy way to see what everyone’s saying about the market on Twitter. What’s powerful here is that StockTwits is becoming a focused community within the messy, random cacophony you find on Twitter — and even better, a community that’s all about helping people make money. It’s also moving beyond the StockTwits site alone, with features like a Firefox browser plugin to enhance what you see within Twitter and integration with blogs built on the WordPress platform.

Co-founder Howard Lindzon says that the current version of StockTwits will remain free, but there will be a premium offering soon. The new funding comes from True Ventures.